If the water you top off with is unboiled tap water, then you're introducing a lot of O2 that way, such that vigorous shaking is probably all you need.
The aquarium pump system = pump + tubing + sanitary filter + tubing + 2 micron SS difussion stone. It takes about 15-20 minutes to get a vigorous aeration.
Or you can go O2 tank + regulator + tubing + .05 micron SS difussion stone for more like 5 seconds.
EDIT: that should be .5 micron, not .05